------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- S Y S T E M . E X C E P T I O N _ T R A C E S -- -- -- -- S p e c -- -- -- -- Copyright (C) 2000-2020, AdaCore -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package provides an interface allowing to control *automatic* output -- to standard error upon exception occurrences (as opposed to explicit -- generation of traceback information using System.Traceback). -- This output includes the basic information associated with the exception -- (name, message) as well as a backtrace of the call chain at the point -- where the exception occurred. This backtrace is only output if the call -- chain information is available, depending if the binder switch dedicated -- to that purpose has been used or not. -- The default backtrace is in the form of absolute code locations which may -- be converted to corresponding source locations using the addr2line utility -- or from within GDB. Please refer to System.Traceback for information about -- what is necessary to be able to exploit this possibility. -- The backtrace output can also be customized by way of a "decorator" which -- may return any string output in association with a provided call chain. -- The decorator replaces the default backtrace mentioned above. -- On systems that use DWARF debugging output, then if the "-g" compiler -- switch and the "-Es" binder switch are used, the decorator is automatically -- set to Symbolic_Traceback. with System.Traceback_Entries; package System.Exception_Traces is -- The following defines the exact situations in which raises will -- cause automatic output of trace information. type Trace_Kind is (Every_Raise, -- Denotes the initial raise event for any exception occurrence, either -- explicit or due to a specific language rule, within the context of a -- task or not. Unhandled_Raise, -- Denotes the raise events corresponding to exceptions for which there -- is no user defined handler. This includes unhandled exceptions in -- task bodies. Unhandled_Raise_In_Main -- Same as Unhandled_Raise, except exceptions in task bodies are not -- included. ); -- The following procedures can be used to activate and deactivate -- traces identified by the above trace kind values. procedure Trace_On (Kind : Trace_Kind); -- Activate the traces denoted by Kind procedure Trace_Off; -- Stop the tracing requested by the last call to Trace_On. -- Has no effect if no such call has ever occurred. -- The following provide the backtrace decorating facilities type Traceback_Decorator is access function (Traceback : Traceback_Entries.Tracebacks_Array) return String; -- A backtrace decorator is a function which returns the string to be -- output for a call chain provided by way of a tracebacks array. procedure Set_Trace_Decorator (Decorator : Traceback_Decorator); -- Set the decorator to be used for future automatic outputs. Restore the -- default behavior if the provided access value is null. -- -- Note: System.Traceback.Symbolic.Symbolic_Traceback may be used as the -- Decorator, to get a symbolic traceback. This will cause a significant -- cpu and memory overhead on some platforms. -- -- Note: The Decorator is called when constructing the -- Exception_Information; that needs to be taken into account -- if the Decorator has any side effects. end System.Exception_Traces;